Even skin color/tone is a major indicia of a healthy looking appearance. Make-up formulas have been designed to mimic a person's skin tones. High loadings of pigments such as titanium dioxide and zinc oxide are optical ingredients necessary for these formulations. These loadings achieve a covering purpose at the expense of inferior tactile sensory properties.
Less pigment-loaded formulas, particularly moisturizers can provide the desired tactile sensory benefits. These formulas, however, do not address facial color issues.
An alternative approach to the matte effect of make-up has been the use of soft focus particles. Here the incoming light is distorted by scattering (lensing). Components of these formulas operate as lenses to bend and twist light into a variety of directions to provide a blurring effect on high-contrast blemishes or spots.
U.S. Pat. No. 5,997,890 (Sine et al.), U.S. Pat. No. 5,972,359 (Sine et al.), and U.S. Pat. No. 6,174,533 B1 (SaNogueira, Jr.) are all directed to topical compositions that provide good coverage of skin imperfections. The solution proposed by these documents is a soft focus effect utilizing a metal oxide with a refractive index of at least about 2 and a neat primary particle size of from about 100 to about 300 nm. Preferred particulates are titanium dioxide, zirconium oxide and zinc oxide.
A significant disadvantage of titanium dioxide, zirconium oxide and zinc oxide is their over-whitening effect upon the skin. An undesirable ashen and patchy appearance is often unfortunately created. Colourants (especially red and/or purple colourants) are able to counter-balance the unnatural whitening effect, but typically even a tiny amount of dye results in heavily-tinted product and we have found that consumers desire moisturizing formulations which do not resemble make-up cosmetics when in-pack.
We have also found that the unwanted ashen/patchy appearance afforded by some pigment systems can be exaggerated on drying. Thus we have recognized a need for compositions which gradually develop more natural skin tone alter application to the skin and concomitant with drying of the product on skin.
US patent application published as US 2009/0155321 A (Conopco, Inc), is directed to a cosmetic composition and method of imparting a healthy appearance to skin which includes using a composition formed with about 0.1 to about 20 percent by weight of the composition of beads, from about 1 to about 80 percent by weight of the beads of a first coloring agent incorporated within a matrix of the beads, and a cosmetically acceptable carrier, the composition having a hue less than 25 degrees, the beads being coated and having an exterior color other than that of the first coloring agent. The beads are said to be relatively unnoticeable within a moisturizer composition but are frangible such that upon being rubbed into the skin, they deliver color effects.
Unfortunately, the present inventors have found that the use of frangible beads as a means of hiding colourants within a formulation has drawbacks. In particular, the beads may not always rupture in a desirable manner and can sometimes leave “streaks” or other uneven regions of color which does not result in an even appearance.
Therefore the present inventors have recognized a need to provide cosmetics which not only deliver a desirable skin appearance but that also impart desirable tactile sensory benefits and/or deliver the in-pack appearance expected of a moisturizer.